My internet connectivity drops about every 15 minutes or so. Comcast cable internet, Linksys 160n wireless router. Happens on two desktops, two laptops, Netflix TV (roku), Vonage phone, etc. "ipconfig /renew" fixes the problem -- temporarily. Reboots, cold starts, etc. don't work. One desktop has Smite game installed, thought this might be a problem, but don't know why. Any thoughts?